Inspection After Disassembly
CYLINDER BLOCK
Inspection After Disassembly
CRANKSHAFT SIDE CLEARANCE
- Using a dial gauge (A), measure the clearance between the thrust bearings and the crankshaft arm when the crankshaft is moved fully forward or backward.
Standard : 0.10 - 0.26 mm (0.0039 - 0.0102 in)
Limit : 0.30 mm (0.0118 in)
- If the measured value exceeds the limit, replace the thrust bearings, and measure again. If it still exceeds the limit, replace the crankshaft.
CONNECTING ROD SIDE CLEARANCE
- Measure side clearance between connecting rod and crankshaft arm using a suitable tool (A).
Standard : 0.20 - 0.35 mm (0.0079 - 0.0138 in)
Limit : 0.50 mm (0.0197 in)
- If the measured value exceeds the limit, replace the connecting rod bearings, and measure again. If it still exceeds the limit, replace the crankshaft also.
PISTON AND PISTON PIN CLEARANCE
Diameter of Piston Pin Bore
- Measure the diameter of piston pin bore using an inside micrometer. Refer to "Standard and Limit" [1][2]Specifications.
Outer Diameter of Piston Pin
- Measure outer diameter of piston pin using a suitable tool (A).
Refer to "Standard and Limit" [1][2]Specifications.
Piston to Piston Pin Clearance (Piston pin clearance) = (Piston pin bore diameter) - (Outer diameter of piston pin)
(A) : Front mark
(B) : Piston pin bore grade
(C) : Piston grade I.D. stamp
(D) : Piston crown I.D. code stamp
(E) : ID mark
Standard: 0.002 - 0.006 mm (0.0001 - 0.0002 in)
- If clearance exceeds specification, replace either or both of piston/
piston pin assembly and connecting rod assembly with reference to specification of each parts.
- Use the piston selection table to replace piston/piston pin assembly. Refer to "How to Select Piston and Bearing" Service and Repair.
- Use the connecting rod bearing selection table to replace connecting rod. Refer to "How to Select Piston and Bearing" Service and Repair.
NOTE:
- The connecting rod small end grade and piston pin hole (piston pin) grade are provided only for the parts installed at the plant. For service parts, no grades can be selected. Only 0 grade is available.
(A) : Oil splash
(B) : Small end diameter grade
(C) : Reference code
(D) : Bearing stopper groove
(E) : Reference code
(F) : Cylinder No.
(G) : Big end diameter grade
- Follow the "CONNECTING ROD BUSHING OIL CLEARANCE (SMALL END)" procedure for the values for each grade at the plant.
PISTON RING SIDE CLEARANCE
- Measure side clearance of piston ring and piston ring groove using a feeler gauge. Refer to "Standard and Limit" [1][2]Specifications.
- If out of specification, replace piston and/or piston ring assembly.
PISTON RING END GAP
- Check if inner diameter of cylinder bore is within specification.
Follow the "PISTON TO CYLINDER BORE CLEARANCE" procedure.
- Insert piston ring (2) to middle of cylinder (B) with piston (1), in the direction shown (A), and measure gap using feeler gauge (C).
Refer to "Standard and Limit" [1][2]Specifications.
- If out of specification, replace piston ring.
CONNECTING ROD BEND AND TORSION
- Check with connecting rod aligner. Refer to "Standard and Limit" [1][2]Specifications.
- If it exceeds the limit, replace connecting rod assembly.
CONNECTING ROD BEARING (BIG END)
- Install the connecting rod cap (1) without the connecting rod bearing installed. After tightening the connecting rod bolt to the specified torque, measure the connecting rod big end inner diameter using an inside micrometer. Refer to "Standard and Limit" [1][2]Specifications.
(A) : Example
(B) : Measuring direction of inner diameter
(2) : Connecting rod
CONNECTING ROD BUSHING OIL CLEARANCE (SMALL END)
Inner Diameter of Connecting Rod (Small End)
- Measure inner diameter of bushing using suitable tool (A). Refer to
"Standard and Limit" [1][2]Specifications
Outer Diameter of Piston Pin
- Measure outer diameter of piston pin using suitable tool (A). Refer to "Standard and Limit" [1][2]Specifications.
Piston Pin to Connecting Rod Bushing Clearance (Small End)
(Piston pin to connecting rod bushing clearance (small end)) = (Inner diameter of connecting rod small end) - (Outer diameter of piston pin)
Standard: 0.005 - 0.017 mm (0.0002 - 0.0007 in)
- If the measured value exceeds the standard, replace the connecting rod assembly and/or piston and piston pin assembly.
(A) : Oil splash
(B) : Small end diameter grade
(C) : Reference code
(D) : Bearing stopper groove
(E) : Reference code
(F) : Cylinder No.
(G) : Big end diameter grade
- If replacing the piston and piston pin assembly, use the "Piston Selection Table" to select the piston corresponding to the applicable bore grade of the cylinder block to be used. Refer to "How to Select Piston and Bearing" Service and Repair.
Factory Installed Parts Grading:
- Service parts apply only to grade 0 (B).
Unit: mm (in)
(A) : Front mark
(B) : Piston pin bore grade
(C) : Piston grade I.D. stamp
(D) : Piston crown I.D. code stamp
(E) : ID mark
CYLINDER BLOCK DISTORTION
- Using a scraper, remove gasket on the cylinder block surface, and also remove oil, scale, carbon, or other contamination.
CAUTION:
Be careful not to allow gasket debris to enter the oil or coolant passages.
- Measure the distortion on the block upper face at some different points in 6 directions using a suitable tool (A).
Limit: 0.1 mm (0.004 in)
- If out of the distortion limit, replace the cylinder block and lower block they are machined together as an assembly.
INNER DIAMETER OF MAIN BEARING HOUSING
- Install the main bearing caps with the main bearings removed and tighten the bolts to the specified torque. Refer to "Disassembly and Assembly" Disassembly And Assembly.
- Using a bore gauge (A), measure the inner diameter of the main bearing housing.
Standard: 58.944 - 58.968 mm (2.3206 - 2.3216 in)
- If out of the standard, replace the cylinder block and lower cylinder block assembly.
NOTE:
These components cannot be replaced as a single unit because they were processed together.
PISTON TO CYLINDER BORE CLEARANCE
Inner Diameter of Cylinder Bore
- Using a bore gauge, measure cylinder bore for wear, out-of-round and taper at 6 different points on each cylinder. (Y and X directions at C, D, and E). The Y axis is in the longitudinal direction of the engine.
NOTE:
When determining cylinder bore grade, measure cylinder bore at (D) position. Refer to "Standard and Limit" [1][2]Specifications.
Standard: Refer to "Standard and Limit" [1][2]Specifications.
Out-of-round : Difference between (Y) and (X).
Taper : Difference between (C) and (E).
Dimension (f) : 10 mm (0.39 in)
Dimension (g) : 60 mm (2.36 in)
Dimension (h) : 120 mm (4.72 in)
- If there are scratches and/or seizure on the cylinder inner wall, hone the inner wall.
Outer Diameter of Piston
- Measure piston skirt diameter using a suitable tool (A). Refer to
"Standard and Limit" [1][2]Specifications.
- Measure point (distance from the top): 37.5 mm (1.476 in).
Piston to Cylinder Bore Clearance
- Calculate by outer diameter of piston skirt and inner diameter of cylinder (direction X, position B).
(Clearance) = (Inner diameter of cylinder) - (Outer diameter of piston skirt).
Standard : 0.010 - 0.030 mm (0.0004 - 0.0012 in)
Limit : 0.08 mm (0.0031 in)
- If it exceeds the limit, replace piston/piston pin assembly.
Reboring Cylinder Bore
1.Cylinder bore size is determined by adding piston-to-bore clearance to piston diameter (A).
Rebored size calculation: D = A + B - C
(D) : Bored diameter
(A) : Piston diameter as measured
(B) : Piston-to-bore clearance (standard value)
(C) : Honing allowance 0.02 mm (0.0008 in)
2.Install lower cylinder block, and tighten to the specified torque. Otherwise, cylinder bores may be distorted in final assembly.
3.Cut cylinder bores.
-When any cylinder needs boring, all other cylinders must also be bored.
-Do not cut too much out of cylinder bore at a time. Cut only 0.05 mm (0.0020 in) or so in diameter at a time.
4.Hone cylinders to obtain specified piston-to-bore clearance.
5.Measure finished cylinder bore for out-of-round and taper.
-Measurement should be done after cylinder bore cools down.
OUTER DIAMETER OF CRANKSHAFT JOURNAL
- Measure outer diameter of crankshaft journals using suitable tool (A).
Standard: 54.955 - 54.979 mm (2.1636 - 2.1645 in)
OUTER DIAMETER OF CRANKSHAFT PIN
- Measure outer diameter of crankshaft pin using a suitable tool.
Standard: 44.956 - 44.974 mm (1.7699 - 1.7706 in)
OUT-OF-ROUND AND TAPER OF CRANKSHAFT
- Measure the dimensions at four different points as shown on each journal and pin using a micrometer.
- Out-of-round is indicated by the difference in dimensions between (X) and (Y) at (A) and (B).
- Taper is indicated by the difference in dimension between (A) and (B) at (X) and (Y).
Standard
Out-of-round (X - Y) : 0.005 mm (0.0002 in)
Taper (A - B) : 0.005 mm (0.0002 in)
CRANKSHAFT RUNOUT
- Place a V-block on a precise flat table to support the journals on both ends of the crankshaft.
- Place a dial gauge (A) straight up on the No. 3 journal.
- While rotating the crankshaft, read the movement of the pointer on the dial gauge (A), the total indicator runout reading.
Limit: Less than 0.05 mm (0.002 in)
OIL CLEARANCE OF CONNECTING ROD BEARING
Method of Measurement
- Install the connecting rod bearings (2) to the connecting rod (3)
and the cap (1), and tighten the connecting rod bolts to the specified torque. Using a inside micrometer measure the inner diameter of connecting rod bearing (B).
(Oil clearance) = (Inner diameter of connecting rod bearing) (Outer diameter of crankshaft pin)
(A) Example
Standard : 0.035 - 0.045 mm (0.0014 - 0.0018 in)
Limit : 0.10 mm (0.0039 in)
- If clearance cannot be adjusted within the standard, grind crankshaft pin and use undersized bearing. Refer to "How to Select Piston and Bearing" Service and Repair.
Method of Using Plastigage
- Remove oil and dust on the crankshaft pin and the surfaces of each bearing completely.
- Cut the Plastigage slightly shorter than the bearing width, and place it in crankshaft axial direction, avoiding oil holes.
- Install the connecting rod bearings to the connecting rod cap, and tighten the connecting rod bolts to the specified torque.
CAUTION:
Do not rotate the crankshaft.
- Remove the connecting rod cap and bearings, and using the scale on the Plastigage bag, measure the Plastigage width.
NOTE:
The procedure when the measured value exceeds the limit is same as that described in the method by calculation.
OIL CLEARANCE OF MAIN BEARING
Method of Measurement
- Install the main bearings to the cylinder block and bearing cap. Measure the main bearing inner diameter with the bearing cap bolt tightened to the specified torque.
(Oil clearance) = (Inner diameter of main bearing) - (Outer diameter of crankshaft journal)
Standard:
No. 1, 3, and 5 journals : 0.012 - 0.022 mm (0.0005 - 0.0009 in)
No. 2 and 4 journals : 0.018 - 0.028 mm (0.0007 - 0.0011 in)
Limit : 0.1 mm (0.004 in)
- If the measured value exceeds the limit, select main bearings referring to the main bearing inner diameter and crankshaft journal outer diameter, so that the oil clearance satisfies the standard. Refer to "How to Select Piston and Bearing" Service and Repair.
Method of Using Plastigage
- Remove oil and dust on the crankshaft journal and the surfaces of each bearing completely.
- Cut the Plastigage slightly shorter than the bearing width, and place it in crankshaft axial direction, avoiding oil holes.
- Tighten the main bearing bolts to the specified torque.
CAUTION:
Do not rotate the crankshaft.
- Remove the bearing cap and bearings, and using the scale on the
Plastigage bag, measure the Plastigage width.
NOTE:
The procedure when the measured value exceeds the limit is same as that described in the "Method by Calculation".
CRUSH HEIGHT OF MAIN BEARING
- When the bearing cap is removed after being tightened to the specified torque with main bearings installed, the tip end of bearing must protrude.
Standard: There must be crush height.
- If the standard is not met, replace main bearings.
OUTER DIAMETER OF LOWER CYLINDER BLOCK BOLT
- Perform only with M10 (0.39 in) bolts.
- Measure outer diameters (d1, d2) at two positions as shown.
- Measure d2 at a point within area (A) as shown.
- When the value of d1- d2 exceeds the limit (a large difference in dimensions), replace the bolt with a new one.
Limit : 0.13 mm (0.0051 in)
OUTER DIAMETER OF CONNECTING ROD BOLT
- Measure outer diameter (d) at position as shown.
- When (d) exceeds the limit (when it becomes thinner), replace the bolt with a new one.
Limit: 7.75 mm (0.3051 in) or less